1. Field of the Invention
The present invention relates to a sanitary napkin which is superior in body fit, and highly effective in preventing leakage of a menstrual blood toward buttocks.
2. Description of the Related Art
When a female during menstruation lies down to sleep while wearing a sanitary napkin, there is the possibility of rearward leakage of the menstrual blood along the gluteal fold of the wearer. Particularly when the wearer lies on her back, the menstrual blood is liable to flow rearwardly along the gluteal fold by gravity, causing the rearward leakage.
As sanitary napkins taking measures to prevent such rearward leakage of the menstrual blood in bed, there have been known ones of which a rear portion can readily fit in the gluteal fold.
For example, Patent Gazette of Japanese Patent No. 2784016 discloses an absorbent article to be used as a sanitary napkin, in which an elastic member disposed in a rear part of a liquid-receiving region is made flexible to fit in the gluteal fold.
On the other hand, Japanese Unexamined Patent Publication No. 2000-189456 discloses an absorbent article to be used as a sanitary napkin, in which an absorbent layer having a first raised portion and a second raised portion. In this absorbent article, the first raised portion is aimed at coming into close contact with a discharging part of the wearer's body, and the second raised portion is aimed at fitting in the gluteal fold. Between the first and second raised portions, in addition, there is provided a flexible region having a stiffness lower than those of the two raised portions, thereby enabling the absorbent article to deform so that the first and second raised portions may fit on the body.
However, in the absorbent article disclosed in Patent Gazette of Japanese Patent No. 2784016, only the measure to make the elastic member of the rear part fit in the gluteal fold is taken, but no measure is taken for fit of the absorbent article against the vaginal opening and its surroundings. Therefore, when the wearer lies on her back in bed, the menstrual blood discharged from the vaginal opening is liable to migrate to the wearer's back directly along the gluteal fold. However, since the gluteal fold extending rearwardly from the anus is so deep, if the menstrual blood flowing rearwardly from the vaginal opening is collected in the fold, it is impossible to certainly prevent the rearward leakage of the menstrual blood only with the measure using the elastic member of the rear part.
In the absorbent article disclosed in Japanese Unexamined Patent Publication No. 2000-189456, on the other hand, the amount of menstrual blood flowing rearwardly in bed can be reduced. by bringing the first raised portion placed forward into close contact with the discharging part. However, since the flexible region is provided between the first and second raised portions, the absorbent article is liable to bend at the flexible region when the wearer's body moves in bed. As a result, the first and second raised portions may possibly move away from the wearer's body or slip off the discharging part and the gluteal fold. In addition, since the flexible region is liable to move away from the wearer's body, a menstrual blood which could not dammed up by the first raised portion may possibly leak sidewardly at the flexible region.